UN300 - less than 300 miles and it's toast

[hamster]

Token didn't last for me, there is a design fault in the screw-in cup creating a moisture trap at the bearing seal. One winter on the Singlespeed then toast.
I'm on a Genetic Karyotype now. One winter survived, fingers crossed for the next...

(edit, had thought the replacement was IRD!)

 

[Ugo51]

So, got a new UN300 and did about 200 miles. Same problem. I felt something loose, thought it was the pedals but no! Also this BB has loose bearing on the non-drive side.
Needless to say, I will not buy a third UN300....

 

[trailstar82]

Oh no, I’ve installed a couple of these 300s and not hearing any good news about them.

Sorry if it’s been asked before, but has anyone successfully dismantled a Un51/71 and replaced the bearings?

 

[Ren Rawbor]

I have a feeling this is going to become more of a pressing (pun semi-intended) issue going forwards & replacing bearings in older quality BBs is something that needs looking into. After all, they put it together so it CAN be taken apart too lol (Honestly, all our bikes here are on cup n cone anyway. More maintenance overall but if you keep up on cleaning/greasing they last OK)

 

[Ugo51]

Bearings might be easy to replace but at that point I prefer to stick with a cup and cone BB.

In the meantime... does anybody want to buy two UN300? Both very low mileage

 

[hamster]

Sorry if it’s been asked before, but has anyone successfully dismantled a Un51/71 and replaced the bearings?

I don't believe its possible as the bearing seems to use the cartridge outer shell. I understand that you can do it with UN91, but of course that's only in a single length. I reckon it's possible with Token, certainly you can with old bling stuff like Real...and of course Royce.

 

[Ren Rawbor]

... does anybody want to buy two UN300? Both very low mileage

Let me guess, you're taking a huge loss at the bargain price they're offered at & you'd keep them but wish to pass them on to benefit the community

 

[Ugo51]

Exactly!
I am that generous....

I just ordered a new UN55. I was tempted to go with the Neco ones as some of you had suggested but then decided to stick with Shimano. Just because I have a UN55 on my Peugeot. Let's see how that goes.

 

[mdvineng]

Hope you're not in the habit of using a jetwash to clean the bike.

 

[Ugo51]

Hope you're not in the habit of using a jetwash to clean the bike.

Definitely not